Suction roll construction



Jan. 31, 1961 J. H. REYNAR 2,959,837

SUCTION ROLL CONSTRUCTION Filed June 10, 1958 3 Sheets-Sheet 1 INVENTORIBY JOHN' H. REYNAR ATTY s,

Jan. 31, 1961, J. H. REYNAR 2,959,837

SUCTION ROLL CONSTRUCTION Filed June 10, 1958 3 Sheets-Sheet 2INVENTOR'. JOHN H. REYNAR BY 87 32 W AI YS- Jan. 31, 1961 J. H. REYNAR I2,969,837

SUCTION ROLL CONSTRUCTION Filed June 10, 1958 3 Sheets-Sheet 3 i A A MW94: 95 94 INVENTORZ JOHN H. R EYNAR ATTYS SUCTION ROLL CONSTRUCTION JohnH. Reynar, Coatesville, Pa., assignor to Layton- Greenfield, Inc.,Wagontown, Pa., a corporation of Pennsylvania Filed June 10, 1958, Ser.No. 741,114

Claims. (Cl. 162-671) This invention relates to a suction roll for aFourdrinier or other type of paper making machine, and is particularlyconcerned with the structure of the suction box within the suction rolland its related and associated parts.

In the prior art, wear has been a considerable problem in the suctionroll of the paper making machine. Wear has been particularly noticeableat the wiper members of the suction box which make the vacuum sealbetween the fixed internal box and the inner surface of the rotatingshell of the roll. More important from the standpoint of replacement orrepair cost is wear of the shell itself which, due to the action of thewiper memhers, is apt to be badly worn in a relatively short time. Thisis particularly serious when a wiper presses against the inside of theshell with uneven pressure over its length causing heavier wear at oneplace than at another. The overall wear, however, has been thought to'be too severe even when wear is even. Although lack of adequatelubrication at the bearing surface of the wiper has been found to be animportant cause of excessive Wear, various ways of minimizing wear havebeen attempted without significant success.

The present invention is directed to improvements which tendsignificantly to minimize the wear in the suction roll of a paper makingmachine. An effort has also been made to make more wear-resistant theparts subject to wear. Moreover, the wear which must inevitably occur isconcentrated at those parts of the device which can be easily andcheaply replaced, and those parts are made easily removable for suchreplacement.

In accordance with the present invention, the suction roll for a papermaking machine is provided in which wear is minimized in several ways.First of all, wherever possible friction is minimized by making thewiper members and other bearing surfaces of a minimum friction material,such as tetrafluoroethylene, using either solid or coated members.Teflon is typical of a small group of resinous materials capable ofproviding its own lubricating eifect, and it is itself an excellentwear-resistant yet resilient product which will maintain a vacuum sealand without excessive wear to itself or the shell even after longperiods of use. Next, all unevenness in the pressure by which the wipermembers are urged against the shell is eliminated. This may be done inat least two ways in accordance with the invention, to wit: One, provideuniform spring means throughout its length, which length isapproximately that of the wiper and, two, pro vide individual springmembers each adapted to supply a pressure in accordance withpredetermined requirements at the seal, which may be uniform along itslength. In the latter case, these spring members are preferably arrangedso that the spring members can transmit their wipers. As noted above thewipers are made of tetrafiuoroethylene or similar low-friction material.They are also made with one or more channels extending the length of thewipers and open to the bearing surface which contacts the shell. Thesechannels are connected with water or other lubricant-supplying conduitswhereby in use lubricant can be fed continuously to the bearing surface.The feeding of lubricant to the bearing surface of the wipers has threeimportant effects: first, it lubricates the surfaces and prevents wearby tending to space them apart by a film of lubricant, second, it sealsthe suction box to the shell in a barrier which prevents passage ofwater and air laterally into the suction box instead of through theshell; and, third, the film of lubricant re-.

duces the noise of the suction roll by providing a buffer between theparts. Additionally, the wipers and their associated structure aredesigned to be readily removable from the suction roll assembly withouttearing down so that they may be replaced as they wear. In thisconnection the lubricant supplying lines are provided with couplingmeans which permits removal and replacement of wipers such that whenevera wiper is in place a good seal prevents leakage of lubricant at theseal.

Finally, the drum itself is preferably composed of a resinous materialwhich has long life and is wear-resistant and which also obviates needfor a composite metal and rubber structure which has provided so muchdifficulty in the past by requiring the rubber and the metal to be boredin an expensive two-step procedure.

Each of these features is applied to the structure of the presentinvention which, in brief, involves, in a paper making machine, asuction roll construction. The suction roll consists of a hollowcylindrical perforated suction roll shell rotatably supported by endbearings. A fixed suction box internal of the suction roll shell isprovided so that the shell rotates relative to it. This suction box hasan opening on the side of the box most closely adjacent to the shell.Deckling means is provided at the opening of the box adjacent the shelland is movable in the direction of elongation of the box and the shellso as to effectively adjust the length of opening of the suction box fordifferent widths of paper. Finally, wiper members associated with thesuctionbox and the deckling means resiliently urged toward and intocontact with the shell are provided.

For a better understanding of these and other features of the presentinvention, reference is made to the following drawings which illustrateone embodiment of the present invention:

' Fig. 1a shows in section one end of the suction roll of a paper makingmachine embodying features of the invention;

force through the wipers to part of the supporting struc- Fig. 1b showsin section the other end of the suction roll of Fig. la;

Fig. 2 is a sectional view taken along line 2-2 of Fig. 1a;

Fig. 3 is an enlarged sectional view taken along line 3--3 of Fig. lashowing one spring arrangement in connection with this particular typeof structure;

Fig. 4 is a sectional view taken along line 44 of Fig. 1b;

Fig. 5 is a sectional view taken along line 55 of Fig. 2;

Fig. 6 is a detailed view showing specific construction of the wipermember;

Fig. 7 is another specific construction showing a preferred typeof wipermember for use with the end closure arrangement;

Fig. 8 is an exploded perspective view showing the aseembly of the topof the suction box;

Fig. 9 is a detailed view showing in cross-section modified form of oneof the wiper members of Fig. 8

Fig. shows a modified form of wiper member in contact with the shell;and

Fig. ll shows a different view of the modified type of wiper member. m

Asis Well known tion roll 'is located in 'a'paper making machine -inposition to receive the pulp afterit has been partially dried, and it isa function of thesuction roll to remove additional water from thecontinuous web as it.passes over the roll. Thisis done by means of a-suctionbox withinthe rotating shell of the suction roll located in such aposition that it will apply a suction over a predetermined segment ofthe roll. Ordinarily, the suction box'is closed on all sides but one,which one side is open adjacent the portion of the roll over whichsuction is to be applied, and the suction action is confined to a'regiondefined by sealing means Whichprovide a vacuum seal between the insideof the rotating shell and the suction box.

Referring first to Figs. la and lb, the two drawings there showa'suction roll which is commonly provided on a paper making machine.Referring toFigs. la and lb, for example, which show the improvedstructure of the applicants invention. it will be seen in'this drawingthat there is employed, at least in the region over which the paperstock passes, a rotatable shell 10 of solid phenolic, petro-chemicalproduct, or other relatively rigid resinous material. The shell isperforated'with a plurality of radially directed holes 11 through whichwater is drawn inwardly from the paper'stock by the internal suctionbox. This solid shell construction eliminates the difficulty experiencedwith the conventional laminar shell of rubber covered metal. The twolayer metal and rubber composite structure presented great difliculty inproviding perforations since they had to be drilled in' two separateoperations. l-Ioles were first drilled in the shell and thereafter theshell rubber cover was put in place. It was necessary to drill holeswhich registered with one another. Drilling holes through the compositestructure was avoided lest it should endanger the bond between the metaland rubber. With integral construction of the present invention,perforations 11 through shell 19 are made by drilling clear through theshell in a one-step operation.

The cylindrical working region ofithe shell, in turn, is bolted orotherwise suitably affixed at each end to hollow, generally cylindricalpieces 12 and 13 including bolt flanges 12a and 113a part of whichissnugly received within the respective ends of tubular shell 10 andpart of which bears against the-end of the fshell whereby bolts parallelto the axis may pass through the flange into the ends of the shell.Smallerdiam'eter parts of the castings provide hollow trunnions 15 and16 for the bearings supporting thewhole shell structure. The trun nions'15 and 16 as shown inFigs. 1a and 1b, are rotatably supported byrollenbearing in supports 23 .and 24 which are provided with pairs ofsealingring gaskets ls, 19, and 21 designed to keep moisture outof'andgrease in the bearings. The bearingsupports are 'connected by sturdyconnection pieces 27 and 28 to the ground by whatever arrangement maybedeemed appropriate. A prime mover (not shown) for rotatably driving therollmay be applied to the end of the shaft 30 in order to cause theperforated shell to rotate.

The suction box within the suction'roll is generally designated ,32 andhas a bottom- 33 and two sidewalls 34 and 35. Thickened portions 36 and,37 partially close the ends of the box and limit the opening to ductsize. The actual ducts 38 and 39 are "fixed by radial end flanges 38aand 39a to the suctionbox in position. to elfectively extend the suctionbox-through the hollow trunnions. These ducts are closed at their end bywalls (not shown) Toward its end ,duct 38 is provided with openings 40into a housing 41 fo'rming part of the connection ductwork to a vacuumpump orother suitable means (not shown) for. reducing. air .pressureflinthegsucto those skilled in the art, thesuction box. Tetrafluoroethyleneor other suitable sealing gasket 41a together with gaskets at othercritical locations keep the ductwork airtight. Extending axially fromenclosure 36 within hollow trunnion 15, the tubular portion 38 is, ofcourse, fixed in position and the hollow trunnion 15 of the shellrotates relative to it and about it. Separation of the relativelyrotating parts is accomplished by a bearing 42 of tetrafiuoroethylene orsimilar low frictional material. -A-similar arrangement may be providedby ring 43 between hollow trunnion 39 and stub duct 44 which is hereterminated in a dead end but ,in other embodiments might be connected toa vacuum system like the other end of the machine. ,The suction box mayvary in shape and "arrangement within the scope of the presentinvention.

Completing the vacuum tight closure are a pair of axially arranged wipermembers 47 and 48 and a pair of end wiper members 49 and 50 extendingbetween them. As may be seen in Fig. 8, wiper members 47 and 48 lie inchannels 51 and 52 whichclosely embrace their sides and are urgedupwardlyby springs 53 and 54 of corrugated form which underlie themembers 47 and 48 in their respective receiving channels. Channels 51and 52 are, in turn, fixed tothe tops of sidewalls 35 and 34. Wipermembers 49 and 50 extend between members 47 and 48. They have topsurfaces'curved to mate exactly with the insidesurface of the shell andlie within axially movable channels 56 and 57 which overlie and contactcovet-plates 58 and 59 which close the top of the suction box at itsends. The slidable channel members 56 and 57 are part of the decklingmeans which permits effectiveadjustment of the width of the suction box,and hence the suction roll, to accommodate different widths of paperstock. 'As seen in detailed Fig. 7, the channel member 56 with its'wipermember 49, like all other channels and associated wipers in the device,provide good air-tight sealing means. This is true provided spacedhelical springs 60 urging the wiper 49 into contact -with the'lshell,and the corresponding springs urging wiper 50 into contact with theshell, are eifective. As seen in'Fig. 8, the-channel arrangement is suchas to assure snug interfitting and air-tightness. Movement of channels56 and 57 is accomplished through rods 62, 63- and their associatedconnection brackets 64 and 65, respectively. Brackets 64 and 65 includeinternally threaded portions 64a and 65a which engage inner oppositelythreaded sleeve portions 67a, 67b on shaft 67. Shaft 67 extends axiallywithin the shell and is supported by a pair of b'rackets 69, and isjournaled in end cover 70. 'The threaded sleeves 67a and 67b,-throughwhich passes rod 67,are madelong enough to facilitate the full intendedtravel of brackets 64 and 65 in the deckling system. 'Ascanbesenin-Figs. la and 1b each of the sleeves 67a'and 67b has an axialbayonet slot forengaging'an 'associatedbayonet pin on rod 67. In theposition shown the pin is engaging the sleeve 67a so that it will turnas rod67 turns, but the pin associated with sleeve 67b is disengaged.Axial movement of the rod to the left will disengage sleeve 67a andengage sleeve 67b. Injthis manner the deckling means at each end of theroll is separately adjustable. Rod 67' is axially adjusted by-pushingand pulling hand wheel 71. Ad-

' justment of the position of channel 56 or channel 57, as

selected, is accomplished by rotation of rod 67 which may bedone by..hand wheel 71, or automatic drive means (not shown)-.which may be appliedat the key stub 73. Stub 73 is at. one end of shaft journaled in cover70 at the other end of which shaft is pinion 74. Pinion 74 mates withand drives main spur gear 76 which is fixed directly .toshaft 67.Bearings for all sliding and rotary parts are advantageously made oftetrafluoroethylene.

Qther. details. and refinements of the invention include such things asthe provision of a'layer of resinous material. such; astetrafiuoroethylene, .having low. friction,

applied to the top surface of the top closuremembers 58 and 59. i 'f Ascan be seen in Figs. 3 and 8, in a preferred construction, the channels51 and 52 rest atop and are fixed to the sidewalls 35 and-34 Thepre-formed channel members are made to receive the wiper members quitesnugly and the wiper members are preferablymade of or contain a resinousmaterial having self-lubrication properties, such astetrafluoroethylene; Alternatively, they may be surface coated with suchmaterial ormay consist of some other solid material suitablyimpregnated. Springs 53 and 54 are unique in structure and appearancehaving a corrugated or S-shaped form o'fthe same general cross sectionthroughout their length so that they apply uniform pressure over thisdistance The width dimensions of these springs is selected to be a majorpart of the channel width. The shape of the bearing surface of the wipermembers 47 and 48 is' preferably made to conform to the contour of. theinside surface of the shell in order to provide a maximum of bearingsurface and no rough edges.

In the tops of wipers 47 and 48 are provided'a pairof axial grooves 78and 79 (see Figs. 3 and 8) which, as

seen in Figs. 3 and 5 are connected by ducts 81 to parallel water supplyconduit 82 extending longitudinally through the wiper. As seen in Fig.5, a suitable coupling means including a plug 83 for connectingdistributing tubing 84 (see Fig. 2) through T 85 to a duct 87 (see Fig.to lubricant supply tubing 86 is provided. A threaded cap 88 is providedat the other end of the duct 82 to close it and prevent leakage. It willbe observed that the lubricant supply system is arranged to by-pass allmovable parts. In Fig. la it will be seen that tubing 86 has anassociated supply valve 89. The lubricant normally employed is water.While it would appear that sufficient water would be available forlubrication in these locations, in practice this proves not to be thecase particularly at the rear wiper after water has been removed fromthe paper. In the prior art insufficient lubrication has accounted formuch wear which is eliminated by this system. Also, as previouslymentioned, the lubricant serves as a vacuum seal and also as a sounddeadening layer.

As seen in Fig. 2, the preferred form of the suction box is notrectangular in cross section but is essentially round in cross section.In this case it is difficult to specify the bounds of the sidewalls andbottom walls, but these are large areas which may be considered tooverlap one another and whose bounds are not necessary to define.

'Fig. 9 shows in cross section a modified form of wiper 48' which may bemolded in two pieces 91 and 92 to avoid the need for boring the channel82. The pieces 91 and 92 may be interlocked or otherwise fitted togetherto afford sufiicient water tightness.

Figs. 10 and 11 show a modified form of spring arrangement in whichnegator springs or fiat spiral springs are used to keep tension uniformat spaced points throughout the length of the device. Here on wiper 48there are aflixed at periodic intervals negator springs 94 which arefixed to the sidewalls of channel 52' and preferably in grooves on theinside surface of the sidewalls with their ends bent back over thesidewalls. The other end of the negator is in a sipral roll either on aspindle attached to the bottom of platform 95 or arranged to bearagainst the bottom of the platform to urge it upward. The sidewalls 52'of the channel are under-cut in this embodiment so that the bottom partof the channel is wider than the top. The platform is approximately thewidth of the bottom part with notches cut away to accommodate springs94. This arrangement provides shoulders 96 which act as stops to limitupward movement of platform 95 under the urging of springs 94 and hencethe upward movement of Wiper 91'. It is characteristic of this type ofspring to provide uniform pull so that{by' careful "preselection andmatching identical'springs will provide equaljliftingforce throughoutthelength'of the-wipers. v

The wiper members 47 and 48 or their corresponding pieces in modifiedstructures are arranged so'thatthey" the roll in one of two generalpositions, such as the one illustrated in Figs. 1a,:1b and 4, =accessmay be had to the wiper members.

As can be seen in Figs. la and 8, one end of each wiper memberterminates adjacent aspring bracket- 99,, which is arranged to providea' stop for the slide members as well as support for the coupling member83 which passes through opening 99a and into the chan-' nels 82 of thewiper. The shoulder 99b in these brackets gives sufficient verticalmovement that the opening 99a may follow movement of the wiper memberswithout difiiculty with respect to couplings. As can'be seen in Fig. 5,the plug coupling 83 is adapted to be snugly received into an enlargedsocket portion of channels 82 wherein it is vertically held in place andpreferably sealed by O-ring 100. The coupling is advantageouslysupported by the bracket 99. A clamping ring 101 which threadablyengages the outer threaded surface of a portion of the coupling member83, clamps the bracket 99 between itself and a shoulder on the couplingmember. This arrangement permits axial sliding of the wiper members awayfrom and toward the coupling to disengage the coupling so that thewipers may be removed and replaced simply by an axial sliding movement.Fig. 6 and Fig. 4 illustrate bracket members 103 at the opposite end ofthe channel member, which are to be adapted to be rotated about asupporting pin 104 away from the position shown in Fig. 6 upon looseningof set screw 105 and rotation in a clockwise direction. All of thisstructure, including the screw 105, may be conveniently reached throughaccess opening 98, and either or both wipers 47 and 48 may be removedand replaced by temporarily displacing brackets 103 and sliding wipersaxially outwardly through the opening 98. Replacement is accomplished bysliding new wipers inwardly through opening 98 into their respectivechannels 51 and 52 and re-positioning the brackets 103 and tighteningthe set screw 105.

Access is afforded within the roll for reaching the deckling mechanicsinside the suction box by access plates 107 at opposite ends of thesuction box and on opposite sides thereof as may be seen in Figs. 1a, lband 2. The whole structure of the suction roll in general is such thatit may be easily assembled and disassembled with a minimum of effort. i

The operation of the suction roll is conventional and, therefore, need.not be described. Modifications within the scope of the claims willoccur to those skilled in the art, and are intended to be within thescope and spirit of the present invention.

I claim:

1. In a paper making machine having a hollow cylindrical perforatedsuction roll shell mounted for rotation about its major axis, anelongated suction box internal of the suction roll shell relative towhich the shell rotates and which is open on one side adjacent to theshell, vacuum producing means adapted to produce a suction within thesuction boX, and sealing means on the suction box resiliently urged intocontact with the internal surface of the shell, said sealing meansincluding longitudinal wiper members, holders for said wiper memberswherein the longitudinal wiper members are loosely held, and resilientmeans independent of the pressure of the lubricant employed acting uponthe wiper members to urge them into contact with the internal surface ofthe shell, the improvement of providing said wiper members withlengthwise conduits entirely within the wiper memhers, and conduitstherefrom to that surface of the wip j r ed aga nst the e l a onnec n ens t coupling the; conduits toa source of fluid under pressure wherebyfluid maybe supplied to the surface oi the wipers contactingthe shell toprovide a lubricant between wiper-and shell, r v

2; The suction roll of; claim 1 in which there are two lo g tudin l iprs, o er t n t e wipers on th klin means, and the lubricant is water.

3. The suction roll or claim 1 in which the two longitudinal wipers areeach removable from one end of the suction roll opposite the end fromwhich connection is made to the source of lubricant through supplylines, said supply lines are supported relative to the suction box andterminated in plug portions so that, upon replacement 015 said wipermembers, sockets at the connection end of the conduits receive andcenter the plugs into proper connections, and self-sealing means areprovided between said plug and socket portions.

4. The structure of claim 1 in which troughs connected to the conduitsare provided in the contact surface over the area to be lubricated.

The structure of claim 4, in which atleast one trough in each of thewiper members runs longitudinally he w per msm e e V References Cited inthe file of this patent [UNITED STATES PATENTS A-968333 M7-55, Teflondemonstrates its versatile properties as an engineering material inthese 9 applications (8 pages).

Pulp and Paper Manufacture, volume 3, McGraw-Hill,

1953, Library of Congress, Card Number 5l-9649, pages

